Central supply systems for providing dialysis liquid (also referred to as dialysate) or dialysis liquid concentrates (also referred to as dialysate concentrates) are installed in some dialysis centers. The centrally manufactured liquids or liquid concentrates are typically delivered via a supply line system to individual treatment stations. Dialysis liquid is used at the treatment stations to purify blood circulating in an extracorporeal blood circuit connected to a dialysis machine. In systems that utilize a dialysis liquid concentrate, the dialysis liquid concentrate is delivered via the supply line and is used to manufacture a dialysis liquid to be used for treatment. The liquid concentrate is supplemented with additional solution components and diluted at the treatment station, which provides the prepared dialysis liquid for blood treatment. The used or spent dialysis liquid is often times directed away from the treatment station via a return fluid line system of the supply circuit and can be disposed of centrally. Alternatively, the spent dialysis liquid can be delivered directly into a drainage system.
A central supply system of the type described above renders many components found in conventional dialysis machines of treatment stations (referred to as “bedside monitors”) unnecessary for manufacturing dialysis liquid. The central supply system can, for example, deliver pre-heated dialysis liquid to the treatment station such that no dialysis liquid temperature setting units are required at the treatment station or such that the treatment stations can be operated at a relatively low power. Degassing units within the dialysis machine can similarly be omitted, as the functionality of these units can be performed by the central supply system.
The installation of bedside monitor systems in dialysis treatment centers results in a need to regularly disinfect the supply system and the individual treatment stations. In some instances, contaminants can enter the line system and spread to a bedside station or to a treatment station. For safety reasons, disinfection programs can be observed to ensure that the total supply system is not contaminated. Disinfection can, in some cases, require a significant amount of time and a large effort depending on the size and construction of the line system.
In certain cases, a sterile filter is disposed between the dialysis station to the supply system in order to reduce the risk of contamination to a central dialysis tank.
In some cases, a buffer tank is provided to prevent a backflow of contaminated liquid into the supply line system. In some instances, ultrafilters can be included within the fluid circuit on the dialysate side of the treatment station to further prevent backflow.
The disinfection process for a dialysis treatment station that is supplied with fresh water by a ring line system can include decoupling the dialysis machine from the fresh water system via a valve control, and then disinfecting the dialysis machine with heat or chemical additives while operating the dialysis machine in a circulation mode.